JP3217281B2 - Robot environment recognition apparatus and control method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-propelled robot that performs tasks such as cleaning or monitoring while moving by itself, and in particular, creates an information map of a working environment so that the robot can travel accurately to a target point. The present invention relates to a robot environment recognition device and a control method thereof.

[0002]

2. Description of the Related Art Generally, a conventional device for optimizing a route of a self-propelled mobile robot is disclosed in Japanese Patent Laid-Open No. 4-365104.
No. 6,086,045. As shown in FIG. 10, a robot optimization path mechanism device 9 disclosed in the above publication is a map storage for storing a map in which an area movable over the entire workplace of the robot is classified as an obstacle and displayed. Part 4
A map generating / updating unit 8 for generating a map corresponding to a situation around the robot and updating the map stored in the map storage unit 4; and a route of a target point using the map stored in the map storage unit 4. And a route generation unit 7 for designing a route that avoids obstacles by using the map stored in the map storage unit 4.

A robot equipped with the above-described optimized route mechanism device 9 has a current position from the self-position recognition unit 2, a position of a target point from the command input unit 1, and a position of a target obstacle from the obstacle recognition unit 6. Data for the state is entered. The route constructed by the route search unit 5 or the route generation unit 7 using the above information is transmitted to the drive unit 3 and the robot moves according to the constructed route. Further, the map generation / update unit 8 stores the current position from the work position recognition unit 2,
The state of the surrounding obstacle is input from the obstacle recognition unit 6 while moving, and a map corresponding to the surrounding situation of the robot is generated, thereby updating the map corresponding to all the work sites stored in the map storage unit 4.

[0004]

By the way, in such a conventional device for optimizing a route, it is not necessary for the robot to have complete information on the workplace at the beginning of the work, and a more efficient route is constructed each time the work is performed. Can cope with changes in the workplace, but the robot should be moved using information such as the current position where the robot is traveling, the position of the target point to be traveled, and the presence or absence of obstacles. There is a problem that the memory capacity increases because the stored maps of all the workplaces should be updated while generating the map according to the state such as the presence or absence.

[0005] In addition, another conventional robot that performs a work only based on information about a work environment, divides a given work space into units of a predetermined size and divides each cell into obstacles. It stores necessary information, such as the presence or absence of a robot, and transmits an ultrasonic or infrared signal transmitted from a signal transmitter (ultrasonic or infrared signal transmitter) provided on a predetermined wall in the robot traveling area to a predetermined position of the robot body. Self-propelled in the traveling area at the beginning of the work while receiving by the signal receiver provided in, or traveling along the wall surface.

At this time, when the signal transmitted from the signal transmitter is received by the signal receiver, a code attached to the position transmitted from the signal transmitter is decoded to automatically create an environmental map, Use to start a given task, such as cleaning or monitoring.

In such a robot environment recognizing method, since only the information on the working environment is stored, the current position of the robot is difficult to grasp accurately, and the given working space is merely a predetermined size. Since information is stored in units of units, there is a problem that the memory capacity increases.

Further, there is another problem that a signal transmitter, which is another external device for transmitting an ultrasonic or infrared signal carrying position information, is required, so that the configuration is complicated and the installation is complicated.

Further, if the drive wheels slip due to the material and condition of the floor surface, the robot cannot reach the signal transmitter accurately, so that the signal received by the signal transmitter cannot be received by the signal receiving unit. However, there is a problem that the execution error is repeated until the transmission signal of the signal transmitter is received by the signal receiving unit while moving to the right and left, and the time for grasping the current position is prolonged.

Therefore, the present invention has been made to solve the above-mentioned various problems, and an object of the present invention is to provide a robot for creating an environmental map with a small memory capacity without an additional external device at the beginning of work. And a control method thereof.

Another object of the present invention is to make it possible for a robot to work while traveling accurately to a target point by using a created environmental map to grasp and correct the current position of the work. To provide a robot environment recognition device and a control method thereof.

[0012]

In order to achieve the above object, a robot environment recognizing apparatus according to the present invention is a self-propelled robot which performs given work while moving by itself, and a driving means for moving the robot. Traveling distance detecting means for detecting a traveling distance of the robot moved by the driving means; direction angle detecting means for detecting a change in traveling direction of the robot moved by the driving means; Obstacle sensing means for sensing the distance to the obstacle and the wall surface, and travel distance data detected by the travel distance detection means and travel direction data detected by the direction angle detection means are input to the current position. And control means for controlling the drive means so that the robot can travel to a target point, and the travel distance detection means Travel distance data has been issued, the traveling direction data detected by the direction angle detecting means,
Memory means for storing environmental information on obstacles and walls sensed by the obstacle sensing means,
The control unit is detected by the obstacle detection unit
Depending on the distance to the front wall of the robot,
Calculate the angle between the robot and the front wall
The robot is vertically aligned with the front wall surface, and the environment information of the working space in which the robot travels is determined based on the travel distance detected by the travel distance detection unit and the separation distance from the wall surface detected by the obstacle detection unit. It is stored in the memory means.

The robot environment recognition control method according to the present invention is the robot environment recognition method for performing a given task while moving within a predetermined traveling area by itself, and the robot environment recognition method detected by the obstacle detection means. A vertical alignment step of calculating an angle between the robot placed in an arbitrary direction and the front wall according to a distance to the front wall to vertically align the robot with the front wall; and moving the robot along the wall. A data collection step of sensing the distance between the front wall surface and the left and right side wall surfaces and collecting necessary data of the blocks, and a map creation step of creating an environmental map by summing up the necessary data of each block collected in the data collection step And characterized by the following.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below in detail with reference to the accompanying drawings. As shown in FIG.
The driving means 10 controls the forward and backward movement and the left and right movement of the robot 1, and the driving means 10 controls the left traveling motor 11 so as to move the robot 1 to the right.
Motor driving unit 11 for driving the robot 1 and the robot 1
And the right motor drive unit 12 that drives the right traveling motor 121 so as to move to the left. Driving wheels (not shown) are attached to the left traveling motor 111 and the right traveling motor 121, respectively.

Further, the traveling distance detecting means 20 detects the traveling distance of the robot 1 moved by the driving means 10, and the traveling distance detecting means 20 is driven by the control of the driving means 10. A left encoder 21 that generates a pulse signal proportional to the rotation speed of the left driving wheel, that is, the rotation speed of the left traveling motor 111, to detect the traveling distance of the robot 1 to the right; And a right encoder 22 that generates a pulse signal proportional to the rotation speed of the right drive wheel driven by the robot 1, that is, detects the travel distance of the robot 1 moving to the left by generating a pulse signal. I have.

The direction angle detecting means 30 detects a change in the traveling direction of the robot 1 moved by the driving means 10, and the direction angle detecting means 30 is a robot moved by the driving means 10. It is a direction angle sensor such as a gyro sensor that detects a change in the traveling direction by detecting the rotational angular velocity of the robot 1 according to the voltage level that changes when the robot 1 rotates.

The obstacle sensing means 40 includes the driving means 10
The obstacle sensing means 40 senses the presence or absence of an obstacle present in the travel route of the robot 1 and the distance to the obstacle H, and also senses the distance to the wall surface W. An obstacle H existing in front of the robot 1 and a first obstacle sensing unit 41 for sensing the distance to the wall W, and an obstacle H existing on the left side of the robot 1 and sensing the distance to the wall W And a third obstacle sensing unit 4 that senses the distance between the obstacle H existing on the right side of the robot 1 and the wall surface W.
And 3.

The first obstacle sensing unit 41 of the obstacle sensing means 40 generates an ultrasonic wave on the front surface of the moving robot 1 and reflects the generated ultrasonic wave against the wall W or the obstacle H. A first ultrasonic sensor 411 for receiving a signal, that is, an echo signal, and sensing a distance to an obstacle H or a wall W positioned in front of the robot 1;
50Hz so that the ultrasonic sensor 411 generates ultrasonic waves.
A first sensor driver 412 that inputs a square wave of the first ultrasonic sensor 411 to the first ultrasonic sensor 411;
It comprises a step-in motor 413 for rotating the motor 11 reciprocally by 180 ° in a desired direction, and a step-in motor drive unit 414 for driving the step-in motor 413.

The second obstacle sensing unit 42 of the obstacle sensing means 40 generates an ultrasonic wave on the left side where the robot 1 moves, and the generated ultrasonic wave hits the wall W or the obstacle H. A second ultrasonic sensor 421 that receives the reflected signal and senses a distance to an obstacle H or a wall W located on the left side of the robot 1, and the second ultrasonic sensor 4
A second sensor driver 422 inputs a 50 Hz square wave to the second ultrasonic sensor 421 so as to generate an ultrasonic wave.

The third obstacle sensing unit 43 of the obstacle sensing means 40 generates an ultrasonic wave on the right side where the robot 1 moves, and the generated ultrasonic wave hits a wall W or an obstacle H. A third ultrasonic sensor 431 for receiving the reflected signal and sensing a distance to an obstacle H or a wall W located on the right side of the robot 1; and a third ultrasonic sensor 4
31 includes a third sensor drive unit 432 that inputs a 50 Hz square wave to the third ultrasonic sensor 431 so as to generate an ultrasonic wave.

In the figure, the control means 50 inputs the traveling distance data detected by the traveling distance detecting means 20 and the traveling direction data detected by the direction angle detecting means 30 at predetermined time intervals, and The current position of the robot 1 is calculated, and data on the obstacle H and the wall W sensed by the obstacle feeling means 40 are input, and the wall W existing in front of and on the left and right of the robot 1 is input.
The left and right side traveling motors are calculated so that the robot 1 can accurately travel to a target point without deviating from a normal trajectory by calculating a distance and an angle to the robot, and controlling a traveling route of the robot 1 according to the information result. 111, 12
1 is a microprocessor for determining the output amount.

Further, the memory means 60 stores the traveling distance data detected by the traveling distance detecting means 20, the traveling direction data detected by the direction angle detecting means 30, and the obstacle detected by the obstacle detecting means 40. Thing H
And environmental information, such as data on the wall surface W, is stored and output to the input / output port of the control means 50 through a buffer.

Referring to FIG. 2, a description will be given of a structural diagram of an environment map created by the robot having the above configuration at the beginning of work. As shown in FIG. 2, an obstacle H (specifically, furniture or the like)
And the room where the wall surface W is present is subdivided into a plurality of blocks on the boundary between the obstacle H and the outline of the wall surface W, and each block is (0, 0) (0, 1) (0, 2). , 0) (1,
1) (1, 2)... (M, n) are given.

Further, each block has necessary data as follows. a is the maximum width of each block in the x-axis direction (X_Span) b is the maximum width of each block in the y-axis direction (Y_S
pan, c and d indicate the origin of the maximum width in the xy direction in each block in absolute coordinates (X_Org, Y_Or)
g) e is the size of each block in the x-axis direction (X_Si
ze) and f are the y-axis sizes (Y_Size) of the respective blocks, g is “valid” for blocks without obstacles H, “invalid” for blocks with obstacles H, and areas removed from rooms. Is displayed as "ignore". For i and j, the origin which constitutes the size in the xy direction in each block is displayed in absolute coordinates {(X_Org, Y_Org)}.

The operation and effects of the robot environment recognition apparatus and the control method configured as described above will be described below. FIG. 3 is a flowchart showing the operation sequence for creating an environment map of the robot according to the present invention. FIG.
Represents a step.

First, when a user turns on an operation switch mounted on a predetermined position of the robot 1, in step S1, a driving voltage supplied from a power supply unit (not shown) is input from the control unit 50, and the robot 1 is turned on. The operation for creating an information map (environment map) for the work environment is started at the beginning of the work while being initialized.

Next, in step S2, the first ultrasonic sensor 411 mounted on the front surface of the robot 1 placed at a predetermined position in the traveling area in an arbitrary direction refers to the front based on the driving of the step-in motor 413. At a predetermined interval
As shown in FIG. 4, an ultrasonic wave is generated on the wall W existing in front of the robot 1 moving while rotating the predetermined interval θt at θ, that is, in front of the robot 1 in the traveling direction. The robot 1 calculates the angle (direction) indicating the distance closest to the front wall W by measuring the distance to the wall W existing in front of the robot 1 by receiving the signal reflected by the robot 1.

An example of calculating the angle between the robot 1 and the front wall surface W will be described with reference to FIG. When measuring the distance to the wall surface W while rotating the first ultrasonic sensor 411 at a predetermined angle, assuming that the k-th direction is perpendicular to the wall surface W, the k−1, k, and k + 1 th The distances d (k-1), d (k), and d (k + 1) in the directions satisfy the following expression.

Cos △ θ · d (k−1) = cos △ θ ·
If d (k + 1) = d (k), cos ^-1 ｛d (k)
/ D (k-1)} = cos ^-1 {d (k) / d (k +
1)｝ = △ θ. If d (k-1) = d (k)
Or, when d (k + 1) = d (k), 0 <cos ^-1 {d (k) / d (k-1)} <{θ 0 <cos ^-1 } d (k) / d ( k-1) It can be inferred that the direction indicating the distance closest to the wall surface W from the direction satisfying｝ <△ θ is closest to the direction k perpendicular to the wall surface W. That is, if the k direction is perpendicular to the wall surface W, the angle θk between the k direction and the front of the robot 1 is
Can be regarded as approximating the angle θ.

Next, at step S3, the control means 5
By inputting a control signal output from 0 to the driving means 10 and driving the right-hand traveling motor 121, the robot 1 is rotated leftward by θk to move the robot 1 to the nearest wall surface W as shown in FIG. In step S4, the control means 50 drives the left traveling motor 111 and the right traveling motor 121 to move the robot 1 so as to be perpendicular to the wall surface, and the second ultrasonic sensor 4
The robot 1 is rotated clockwise by 90 ° so that the robot 21 faces the wall surface W and stops.

At this time, the block number is defined as (0, 0), the direction is defined as + x direction, and the position is defined as (0, 0). The first, second, and third ultrasonic sensors 411, 421, and 431 transmit the robot 1 Ultrasonic waves are respectively generated on the moving front wall surface W and the left and right side wall surfaces W, and the ultrasonic waves collide with the front wall surface W and the right and left side wall surfaces W to receive reflected signals and receive the front wall W.
And outputs the detected separation distance data to the control means 50.

Therefore, the control means 50 sets the maximum width of each block in the x- and y-axis directions (X_Sp
an, Y_Span) and the origin which constitutes the maximum width in the xy axis direction in each block is displayed in absolute coordinates (X
_Org, Y_Org) is obtained and recorded in block 0,0.

Next, in step S5, the driving means 10 controls the left and right traveling motors 111, 12 under the control of the control means 50.
When the robot 1 is driven, the robot 1 travels along the wall surface W while maintaining a predetermined distance from the wall surface W, as shown in FIG.

While the robot 1 is traveling along the wall surface W, the process proceeds to step S6, where the second and third ultrasonic sensors 42
From the first and the fourth, the second and third sensor driving units 422 and 43
2 generates an ultrasonic wave on the left or right wall surface W where the robot 1 moves, receives the signal reflected by the ultrasonic wave hitting the left or right wall surface W, and causes the left or right wall of the robot 1 to move on the wall surface. The distance from W is sensed and the distance data is output to the control means 50.

Thus, the control means 50 determines whether or not the distance of the left or right wall surface sensed by the second and third ultrasonic sensors 421, 431 has changed by a predetermined amount or more, and the distance of the left or right wall surface is determined. If the change is not large (NO), the process proceeds to step S7, and it is determined whether or not the robot 1 approaches the front wall surface W while traveling along the wall surface W.

If the result of determination in step S7 is that the robot 1 does not approach the front wall surface W (NO),
Proceeding to step S8, it is determined whether or not the robot 1 has returned to the initial position where the first travel was started while traveling along the wall surface W. If the robot 1 has not returned to the initial start position (NO), the process returns to step S5. Return Step S5 and subsequent operations are repeated.

If the result of determination in step S8 is that the robot has returned to the initial start position (when YES), the travel of the environment map should be terminated, so the flow proceeds to step S9 where the robot 1 is stopped. In step S10, the environment map creation travel is completed while all the necessary data of each block is filled using the block data obtained up to the present to arrange the block data.

On the other hand, if the result of determination in step S6 is that the distance between the left and right wall surfaces has changed significantly (YES), it is determined that the robot 1 has moved to a new block, and the flow proceeds to step S61. Then, the robot 1 is stopped.

Next, in step S62, when it is confirmed that the distance to the left or right wall surface W is larger than a predetermined distance from the time of the first departure, as shown in FIG. 0, the process proceeds to step S63, and the first, second, and third ultrasonic sensors 411,
At 421 and 431, the distance to the front wall surface W and the distance to the left and right side wall surfaces W are sensed, and the sensed distance data is output to the control means 50.

Therefore, in step S64, the control means 5
0 is the first, second, third ultrasonic sensors 411, 421, 4
X_Sp is inputted with the distance data sensed by 31
An, Y_Span, X_Org, and Y_Org data are obtained and recorded in the current blocks 1 and 0, and the process returns to step S5 to repeat the operations from step S6.

If the result of determination in step S7 is that the robot 1 has approached the front wall surface W (YES).
In step S71, the robot 1 is stopped and
In step S72, when it is confirmed that the robot 1 approaches the front wall surface W, as shown in FIG. 7, the current blocks 1, 0 of the robot 1 are recognized, and the process proceeds to step S73. The robot 1 is rotated clockwise by receiving the output control signal and driving the left traveling motor 111.

At this time, in step S74, the first, second, and third ultrasonic sensors 411, 421, and 431 sense the distance to the front wall surface W and the distance to the left and right side wall surfaces W, and transmit the sensed distance data. Output to control means 50.

As a result, in step S75, the control means 5
0 is the first, second, third ultrasonic sensors 411, 421, 4
X_Sp is inputted with the distance data sensed by 31
An, Y_Span, X_Org, and Y_Org data are obtained and recorded in the current blocks 1 and 0, and the process returns to step S5 to repeat the operations from step S6.

On the other hand, when the robot 1 is stopped along the wall W while the distance to the left wall W is greatly changed while traveling along the wall W, if the distance to the left wall W is larger than the previous distance,
After recording the block data, the target point is 50c from the boundary area
Then, as shown in FIG. 8, when traveling is resumed and traveling to the target point is completed, the vehicle rotates 90 ° to the left and resumes the next step.

When the traveling direction is the -x or -y direction and the block is moved, the new block number becomes 0.
It is determined whether the size is smaller than 0. If the size is smaller than 0, all blocks created up to the present are moved in the + direction, and a new block is assigned to C, 0.

Next, with reference to FIG. 9, a description will be given of a method of correcting the current coordinates using the environment map while the robot 1 travels the given route when the environment map is created.

The robot 1 receives the traveling distance data detected by the traveling distance detecting means 20 and the traveling direction data detected by the direction angle detecting means 30 at predetermined time intervals while traveling on the given route. Correct the current position of 1. For example, when the traveling direction is the + x direction and the current position is x, y, x, y on the environment map
Search for the block to which belongs.

At this time, the distance between the front wall surface W sensed by the first ultrasonic sensor 411 and the center of the robot 1 is Ic, the right wall surface W sensed by the third ultrasonic sensor 431 and the center of the robot 1 If the distance to Ir is
The actual position x ', y' of the robot 1 is calculated as follows. x '= X_Org + X_SPaN-Icy' = Y_Org + Ir

The actual position x ', calculated as described above,
y ′, traveling distance detecting means 20 and direction angle detecting means 3
If the position coordinate calculated by accumulating the data detected by 0 is larger than a predetermined value, x and y are corrected to x 'and y'.

The above-described operation is continued while the robot 1 is traveling, so that the robot can smoothly perform the given operation while traveling accurately to the target point.

[0051]

As described above, according to the robot position recognition apparatus and the control method thereof according to the present invention, an environment map is created in a small memory capacity without an external device at the beginning of work, and the environment map is created. By utilizing the current position during work and making corrections, the robot has an excellent effect of performing work while traveling accurately to a target point.

[Brief description of the drawings]

FIG. 1 is a control block diagram of a robot environment recognition device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an environment map creation structure of a robot according to an embodiment of the present invention.

FIG. 3 is a flowchart showing an environment map creation operation sequence of the robot according to the present invention.

FIG. 4 is an explanatory diagram for calculating an angle with respect to a front wall surface of the robot according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a wall traveling of the robot according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a new block movement of the robot according to an embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a state in which the robot according to the embodiment of the present invention approaches a front wall surface.

FIG. 8 is an explanatory diagram illustrating a state in which the distance between the robot and the left wall surface according to the embodiment of the present invention changes.

FIG. 9 is an explanatory diagram for correcting a current position of a robot according to an embodiment of the present invention.

FIG. 10 is a control block diagram of a conventional robot optimization route mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Drive means 11 Left motor drive part 12 Right motor drive part 20 Travel distance detection means 21 Left encoder 22 Right encoder 30 Direction angle detection means 40 Obstacle sensing means 41 First obstacle sensing part 42 Second obstacle sensing part 43 third obstacle sensing unit 50 control unit 60 memory unit 411 first ultrasonic sensor 412 first sensor drive unit 413 step-in motor 414 step-in motor drive unit 421 second ultrasonic sensor 422 second sensor Drive unit 431 Third ultrasonic sensor 432 Third sensor drive unit

Continuation of the front page (56) References JP-A-63-131207 (JP, A) JP-A-7-271435 (JP, A) JP-A-60-93522 (JP, A) JP-A-6-131043 (JP) JP-A-8-171416 (JP, A) JP-A-63-156203 (JP, A) JP-A-1-180010 (JP, A) (58) Fields studied (Int. Cl. ⁷ , DB Name) B25J 13/08 B25J 5/00 G05D 1/02

Claims (5)

(57) [Claims] 1. A self-propelled robot that performs a given task while moving by itself, a driving unit that moves the robot, a traveling distance detection unit that detects a traveling distance of the robot moved by the driving unit, Direction angle detecting means for detecting a change in the traveling direction of the robot moved by the driving means; obstacle sensing means for sensing the distance to an obstacle and a wall in an area where the robot travels; and the traveling distance detecting means. Control means for calculating the current position of the robot based on the travel distance data detected by the control unit and the travel direction data detected by the direction angle detection means to control the drive means; and Traveling distance data, traveling direction data detected by the direction angle detecting means, Memory means for storing environmental information on the obstacle and the wall surface, wherein the control means senses the obstacle information by the obstacle sensing means.
Depending on the distance to the front wall of the robot,
Calculate the angle between the robot and the front wall
The robot is vertically aligned with the front wall surface, and the environment information of the working space in which the robot travels is determined based on the travel distance detected by the travel distance detection unit and the separation distance from the wall surface detected by the obstacle detection unit. An environment recognition device for a robot, wherein the environment is stored in the memory means. 2. The robot environment recognition apparatus according to claim 1, wherein the control unit sorts a work space in which the robot travels into a plurality of blocks along a boundary between an obstacle and a wall surface. 3. The system according to claim 1, wherein the control unit stores necessary data of environmental information in each of a plurality of divided work spaces in which the robot travels.
An environment recognition device for a robot according to item 1. 4. A method for recognizing an environment of a robot performing a given task while moving within a predetermined traveling area, wherein the robot moves in an arbitrary direction according to a distance to a front wall surface of the robot detected by an obstacle detecting means . A vertical alignment step of calculating an angle between the placed robot and a front wall surface to vertically align the robot with the front wall surface; and A data collection step of sensing the distance of the side wall surface to collect necessary data of the blocks, and a map creating step of creating an environmental map by combining the necessary data of the respective blocks collected in the data collection step. Characteristic robot environment recognition control method. 5. The robot environment recognition control method according to claim 4, wherein the robot corrects the current position in the operation according to the environment map created in the map creation step.